No, the SpyX does not need an SD card in order to use or watch live feed. However, if you need to record and save the videos you will need to purchase one. SD Cards are available at All Trends USA.
I can say that it's worth every dollar that I spent on it. I intended to buy this to monitor my son and daughter if they are doing odd things that could destroy their future. But what I've seen on my phone is so shocking. My young daughter is hooking up with the guy next door, and my son is drinking alcohols. I can't believe what they did!! I confronted them and send them my proof, they were shock and annoyed that I caught all their nagging actions.